The present invention relates generally to the field of electronic transaction processing via IP telephony, and more specifically to least cost call routing in a mixed packet and circuit switched network in an automatic call distribution environment.
Packet Switched networks are viewed in the telephony art as a very efficient mechanism for transmitting digitally encoded voice. With the advent of standards for signaling and compression, it appears that a new world-wide standard is emerging which may reduce costs for carriers by simplifying interconnection, avoiding international regulatory costs and barriers, and utilizing less bandwidth for voice calls.
The standards that are emerging for packet switching are defined collectively as H.323. These standards are colloquially known as Voice over IP, or commonly shortened to VoIP. The standards define methods for establishing telephone calls (H.245/Q.931) with compressed audio (Q.723.2). These standards are all available from the International Telecommunications Union (ITU) and are incorporated herein by reference.
Data networking companies such as Cisco of San Jose Calif. produce products that conform to these standards, such as the Cisco 5300 Router. These products can be used to convert traditional telecommunications transport such as T1 with channel associated signaling or common channel signaling to H.245/Q.723.2 and back. Thus traditional voice is routed over IP networks efficiently. By incorporating other network elements such as packet switches, it is believed that new networks which carry voice and data efficiently will replace and/or compete with today""s telecommunications transit networks.
Large packet switched networks are excellent at routing packets from source to destination. With the inclusion of the QoS (Quality of Service) and other mechanisms to guarantee quality and performance, these networks have become effective mechanisms for transporting voice as well as data.
With the advent of H.323 standards, a gatekeeper concept was developed which permits a form of telephone signaling (Q.931) over packet switched networks. The gatekeepers were added to perform several functions. One function is to provide access control to resources managed by the gatekeeper. Another function is to provide addressing and allocation services to enable circuit based signaling protocols to work. Thus Q.931 (ISDN Call Control) can be used to establish calls with a gatekeeper.
The gatekeeper mechanism can perform sufficiently in many cases. However, drawbacks are believed to exist in today""s H.323 VoIP networks. In particular, the standard mechanisms for Least Cost Routing and selection of a gatekeeper are inadequate because circuit availability, on the PSTN side of the gateway, is unknown to the gatekeeper. In other words, a gatekeeper does not know when an apparently unused PSTN circuit is in fact being used, thereby decreasing the likelihood that available bandwidth will be used optimally.
Automatic Call Distributors (ACD) are specialized phone systems used for handling many incoming calls. Once used only by airlines, rent-a-car companies, and hotel chains, ACDs are now used by numerous companies facing a heavy load of incoming calls (e.g., order taking, dispatching of service technicians, taxis, railroads, help desks, and answering technical questions).
An ACD performs four functions. First, it will recognize and answer an incoming call. Second, it will look in its database for instructions on what to do with that call. Third, based on the instructions found, it will send the caller either a recording asking the caller to continue to hold the line, or to a voice response unit (VRU). Fourth, it will send the call to an agent as soon as that agent has completed his or her previous call, and/or the caller has heard a prerecorded hold message.
The term Automatic Call Distributor arose from the device""s function of distributing incoming calls in some logical pattern to a group of operators. That pattern might be Uniform (i.e., distribute the work uniformly) or it may be Top-Down (i.e., the same agents in the same order get the calls and are kept busyxe2x80x94the ones on the top are kept busier than the ones on the bottom). Alternatively, the pattern may include specialty routing, where the calls are routed to answerers who are most likely to be able to help the caller.
While distributing calls logically is the function most commonly associated with an ACD, it is not the ACD""s only function. Larger ACDs are used in call centersxe2x80x94a facility where calls are answered and made. A call center will typically have several people (also called agents), an ACD, and a computer for order-entry and look up on customers"" orders.
Some call centers are further identified as being in-bound call centers and/or out-bound call centers. In-bound call centers only process received calls. Typical applications include catalog sales, customer service, ticket sales, etc. Out-bound call centers only process calls initiated within the out-bound center. Typical applications include telephone sales, fund-raising and general solicitation.
Existing ACD systems provide status reports and real time monitors to provide management and maintenance of call handling, call duration and call resource capabilities, and provide supervisor monitoring capability. Monitoring allows a group supervisor to listen in on conversations to check for correct implementation of procedures. Existing ACD systems provide for links via data communication channels to customers"" Management Information Systems to select caller related data and to assist in delivering calls to agents.
However, all existing ACD systems known to the inventors fail to provide call distribution to agents via packet switched networks. Furthermore, existing ACD systems do not provide call distribution via packet switched networks using mechanisms to detect, in real time, changes in circuit availability on the PSTN side of a gateway.
To address a shortcoming in the available art, the present invention transports, in real time, the xe2x80x9csubscriber sessionxe2x80x9d to a foreign point of presence offering the complete set of features and data remotely that are available when accessing the home system directly.
To address another shortcoming in the available art, the present invention provides a system and method that promotes least cost carrier selection across a packet switched network using mechanisms to detect, in real time, changes in circuit availability on the PSTN side of a gateway.
To address a further shortcoming in the available art, the present invention provides a system and method that promotes least cost routing through a packet switched network in an automatic call distribution environment.
To address still another shortcoming in the available art, the present invention provides a mechanism for selecting the least cost route with a reasonably high certainty that a circuit will be available.
To address yet another shortcoming in the available art, the present invention provides a mechanism for managing bandwidth to various endpoints in the network.
Briefly stated, the present invention provides a method and system for managing a large network of switching end-points to route calls by time of day and day of week over a packet switched network (ATM or Voice over IP). The preferred management mechanisms determine circuit and location availability and include means for removal and replacement of circuits from network-wide service, even in a private, packet-switched network. In an automatic call distribution environment, the method is an economical and efficient process for facilitating a caller""s ability to access users in workgroups wherein the users utilize either wired or wireless communications tools. Users are chosen via a rule-based selection process including access to a database of users, caller-screened information, and circuit and location availability.
An advantage of the present invention provides a mixed circuit and packet switched system that includes a packet switched network, a circuit switched network having a plurality of available circuits, and a gateway interconnecting the packet switched network and the circuit switched network. The system also includes a gatekeeper that is in communication with the gateway such that the gatekeeper controls a flow of data through the gateway. The system further includes an SMP in communication with the gatekeeper and the circuit switched network such that the SMP prompts the gatekeeper to permit the flow of data through the gateway if the SMP detects a predetermined number of available circuits in the circuit switched network.
Another advantage of the present invention provides a method for routing a call from a local service switching point to a remote service switching point via a packet switch network interconnected to the remote service switching point by a gateway and a gatekeeper controlling call pathways through the gateway to the remote service switching point, the method including the steps of providing the local service switching point with a record identifying a plurality of carriers serving the remote service switching point, the record including a cost for using each identified carrier and a number of available circuits in each identified carrier, receiving a call and destination number at the local service switching point, and selecting a carrier from the record, the selected carrier having a predetermined number of available circuits that can connect the received call to the destination number for the lowest cost.
Yet another advantage of the present invention provides a system for routing a call from a local service switching point to a remote service switching point via a packet switched network interconnected to the remote service switching point by a gateway and a gatekeeper controlling call pathways through the gateway to the remote service switching point, the system including means for providing the local service switching point with a record identifying a plurality of carriers serving the remote service switching point, the record including a cost for using each identified carrier and a number of available circuits in each identified carrier, means for receiving a call and destination number at the local service switching point, and means for selecting a carrier from the record, the selected carrier having a predetermined number of available circuits that can connect the received call to the destination number for the lowest cost.
A further advantage of the present invention provides a mixed circuit and packet switched system, the system including a packet switched network, a circuit switched network having a plurality of carriers, each carrier containing a dynamically varying number of available circuits, a plurality of service switching points in communication with the circuit switched network, each service switching point associated with a carrier such that each service switching point can direct a telephone call over an available circuit in the associated carrier, each service switching point containing a global circuit availability record, the global circuit availability record providing circuit availability for every carrier associated with the plurality of service switching points, a plurality of gateways interconnecting the packet switched network and the circuit switched network, each gateway in communication with a service switching point such that a telephone call can be carried between the service switching point and the packet switched network via the gateway, a plurality of gatekeepers, each gatekeeper in communication with a gateway such that each gatekeeper controls a connection of a telephone call between the packet switched network and the circuit switched network via the gateway, each gatekeeper in communication with a service switching point such that the gatekeeper permits the connection of the telephone call through the gateway in response to a prompt from the service switching point, and wherein a first service switching point receives an incoming call on an associated carrier and directs the received call, via the packet switched network, to a gateway in communication with a second service switching point after prompting a gatekeeper in communication with the gateway, the first service switching point selecting the second service switching point from the plurality of service switching points based on a global circuit availability record contained in the first service switching point.
A still further advantage of the present invention provides a system for routing a call via a packet switched network having a gateway and a gatekeeper controlling call pathways through the gateway, the system including a remote service switching point, a local service switching point in communication with the remote gateway and the remote gatekeeper via the packet switched network, the local service switching point containing a global record identifying a plurality of carriers that serve the remote service switching point, the global record including a cost of using each identified carrier and a number of available circuits in each identified carrier, and wherein the local service switching point selects a carrier from the global record in response to receiving an incoming call and a destination number, the selected carrier having a predetermined number of circuits that can connect the incoming call to the destination number for the lowest cost.